2 * 8088flex TMV video decoder
3 * Copyright (c) 2009 Daniel Verkamp <daniel at drv.nu>
5 * This file is part of Libav.
7 * Libav is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
12 * Libav is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with Libav; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
24 * 8088flex TMV video decoder
25 * @author Daniel Verkamp
26 * @see http://www.oldskool.org/pc/8088_Corruption
32 #include "libavutil/internal.h"
36 typedef struct TMVContext {
40 static int tmv_decode_frame(AVCodecContext *avctx, void *data,
41 int *data_size, AVPacket *avpkt)
43 TMVContext *tmv = avctx->priv_data;
44 const uint8_t *src = avpkt->data;
46 unsigned char_cols = avctx->width >> 3;
47 unsigned char_rows = avctx->height >> 3;
48 unsigned x, y, fg, bg, c;
51 avctx->release_buffer(avctx, &tmv->pic);
53 if (avctx->get_buffer(avctx, &tmv->pic) < 0) {
54 av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
58 if (avpkt->size < 2*char_rows*char_cols) {
59 av_log(avctx, AV_LOG_ERROR,
60 "Input buffer too small, truncated sample?\n");
65 tmv->pic.pict_type = AV_PICTURE_TYPE_I;
66 tmv->pic.key_frame = 1;
67 dst = tmv->pic.data[0];
69 tmv->pic.palette_has_changed = 1;
70 memcpy(tmv->pic.data[1], ff_cga_palette, 16 * 4);
72 for (y = 0; y < char_rows; y++) {
73 for (x = 0; x < char_cols; x++) {
77 ff_draw_pc_font(dst + x * 8, tmv->pic.linesize[0],
78 ff_cga_font, 8, c, fg, bg);
80 dst += tmv->pic.linesize[0] * 8;
83 *data_size = sizeof(AVFrame);
84 *(AVFrame *)data = tmv->pic;
88 static av_cold int tmv_decode_init(AVCodecContext *avctx)
90 avctx->pix_fmt = AV_PIX_FMT_PAL8;
94 static av_cold int tmv_decode_close(AVCodecContext *avctx)
96 TMVContext *tmv = avctx->priv_data;
99 avctx->release_buffer(avctx, &tmv->pic);
104 AVCodec ff_tmv_decoder = {
106 .type = AVMEDIA_TYPE_VIDEO,
107 .id = AV_CODEC_ID_TMV,
108 .priv_data_size = sizeof(TMVContext),
109 .init = tmv_decode_init,
110 .close = tmv_decode_close,
111 .decode = tmv_decode_frame,
112 .capabilities = CODEC_CAP_DR1,
113 .long_name = NULL_IF_CONFIG_SMALL("8088flex TMV"),